Transepithelial photorefractive keratectomy for low to moderate myopia in comparison with conventional photorefractive keratectomy

Abstract

Purpose:To compare the effectiveness, safety and stability of the results of transepithelial photorefractive keratectomy (tPRK) with conventional photorefractive keratectomy (PRK) for low to moderate myopia.Methods:In this prospective non-randomized case-control study, patients with low to moderate myopia were assigned to the tPRK group (cases) or the PRK group (controls). In the tPRK group, eyes were treated using the Amaris excimer laser (SCHWIND eye-tech-solutions GmbH and Co. KG, Germany). Outcome measures included postoperative pain using McGill Pain Questionnaire, epithelial healing time, uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), manifest refraction, and safety and efficacy indexes which were compared between the study groups.Results:Three hundred forty eyes of 170 patients were enrolled in this study. Each study group comprised of 170 eyes of 85 patients. There was a significant difference between the two groups regarding the postoperative pain scores in favor of the tPRK group (P = 0.04). The tPRK group had a shorter epithelial healing time than the conventional PRK group postoperatively (P = 0.01). Mean UCVA was significantly better in the case group than in the control group at the postoperative month 2 (P = 0.01). Regarding the safety and efficacy indexes, the tPRK group had better results than the conventional PRK group (P < 0.01 for both comparisons).Conclusion:Transepithelial PRK seems to be superior to conventional PRK for treatment of low to moderate myopia in terms of postoperative pain, epithelial healing time, visual recovery and safety and efficacy indexes.

Myopia

“…This approach has the advantage of not requiring the creation of a corneal flap and is less likely to induce dry eyes after treatment than LASIK. Several options to remove the epithelium exist, including photorefractive keratectomy using mechanical removal 248 , epipolis laser in situ keratomileusis using a special microkeratome 249,250 , laser-assisted subepithelial keratectomy using alcohol 251 and transepithelial photorefractive keratectomy using an excimer laser 252 . The outcomes of surface ablation are similar to those of LASIK, but the removal of the corneal epithelium can result in more patient discomfort after surgery during recovery of the corneal epithelium 248,253 .…”

Comparison of clinical results between trans-PRK and femtosecond LASIK for correction of high myopia

“…This avoided the need for alcohol epithelial debridement or mechanical removal of the epithelium during PRK [7,8]. TPRK requires only one-step removal of the epithelium and stroma, has no instrument contact with the cornea, takes less surgical time, less postoperative pain, faster wound healing and faster visual recovery than conventional PRK [9].…”

Real-world Comparison of StreamLightTM&nbsp;trans-PRK and Conventional PRK&nbsp;With Regard to Refractive Outcome, Wound Healing, Pain Intensity and Visual Recovery Time

“…The shorter epithelial healing time after tPRK observed in our study has been shown in other clinical studies evaluating tPRK treatments performed with other nomograms and other laser systems. Fadlallah et al observed an average period to complete healing of 2.5 days in the tPRK group versus 3.7 days in the conventional PRK group while Naderi et al reported 2.9 days and 3.3 days respectively [11,13]. Although these results were obtained in different studies and therefore cannot be directly compared, it still has to be noted that in our study complete closure of the epithelium after StreamLight TM tPRK was achieved in average after 46 hours, i.e.…”

“…Moreover, patients evaluated their subjective maximum pain intensity level within the rst four days after surgery on a numeric pain rating scale (0-15) which was completed by the patients themselves. Accordingly, pain could be rated as low (1-5), high (6-10) or very high (11)(12)(13)(14)(15). Wound healing was followed during daily slit lamp examinations until day 4.…”